diff --git a/package.json b/package.json
index ef6d88e..8915fa8 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gawk",
-  "version": "3.2.2",
+  "version": "3.3.0",
   "description": "Observable JavaScript object model",
   "main": "./dist/index.js",
   "author": "Chris Barber <chris@cb1inc.com> (https://github.com/cb1kenobi)",
diff --git a/src/index.js b/src/index.js
index 012794a..fd56ce0 100644
--- a/src/index.js
+++ b/src/index.js
@@ -432,7 +432,7 @@ gawk.watch = function watch(subject, filter, listener) {
  * Removes a listener from the specified gawked object.
  *
  * @param {Object|GawkObject|Array|GawkArray} subject - The object to unwatch.
- * @param {Function} listener - The function to call when something changes.
+ * @param {Function} [listener] - The function to call when something changes.
  * @returns {GawkObject|GawkArray} Returns a gawked object or array depending on
  * the input object.
  */
@@ -441,13 +441,20 @@ gawk.unwatch = function unwatch(subject, listener) {
 		throw new TypeError('Expected source to be a GawkArray or GawkObject');
 	}
 
-	if (typeof listener !== 'function') {
-		throw new TypeError('Expected listener to be a function');
+	if (listener) {
+		if (typeof listener !== 'function') {
+			throw new TypeError('Expected listener to be a function');
+		}
+		subject.__gawk__.listeners.delete(listener);
+		subject.__gawk__.previous.delete(listener);
+	} else {
+		// remove all listeners
+		for (const [ listener, filter ] of subject.__gawk__.listeners) {
+			subject.__gawk__.listeners.delete(listener);
+			subject.__gawk__.previous.delete(listener);
+		}
 	}
 
-	subject.__gawk__.listeners.delete(listener);
-	subject.__gawk__.previous.delete(listener);
-
 	return subject;
 };
 
diff --git a/test/test-watch.js b/test/test-watch.js
index 81a0ac7..7ed34f0 100644
--- a/test/test-watch.js
+++ b/test/test-watch.js
@@ -546,10 +546,6 @@ describe('gawk.unwatch()', () => {
 	});
 
 	it('should fail to unwatch with non-function listener', () => {
-		expect(() => {
-			gawk.unwatch(gawk({}));
-		}).to.throw(TypeError, 'Expected listener to be a function');
-
 		expect(() => {
 			gawk.unwatch(gawk({}), 'foo');
 		}).to.throw(TypeError, 'Expected listener to be a function');
@@ -575,6 +571,29 @@ describe('gawk.unwatch()', () => {
 		expect(count).to.equal(2);
 	});
 
+	it('should unwatch all listeners', () => {
+		const gobj = gawk({});
+		let count = 0;
+
+		gawk.watch(gobj, () => {
+			count++;
+		});
+
+		gawk.watch(gobj, () => {
+			count++;
+		});
+
+		gobj.a = 'b';
+		gobj.c = 'd';
+
+		gawk.unwatch(gobj);
+
+		gobj.e = 'f';
+		gobj.g = 'h';
+
+		expect(count).to.equal(4);
+	});
+
 	it('should unwatch GawkArray changes', () => {
 		const garr = gawk(['a']);
 		let count = 0;